Various LED light strings have been proposed for decorative illumination purposes. U.S. Pat. Appln. Pub. No. US2009/0189533 (Hsu), for example, discloses an LED-based light string formed with multiple, dual colored LED lamps and a controller for coupling the LED light string to the power supply. According to one preferred embodiment in Hsu, FIG. 4 discloses a light string in which two LED lamps of different colors are set within a single body. The body is shown to have two connection leads, and the two LED lamps are electrically connected within the body such that one LED lamp illuminates when a positive DC voltage is applied to the two leads of the body and the other LED lamp illuminates when a negative DC voltage is applied to the two leads of the body. Multiple bodies are then electrically connected in series so as to create a single string of LED lights. Claim 3 of Hsu further states that the controller can control only one or the other of the two LEDs within the body to emit a single color, or can control both alternately to emit both colors. However, Hsu does not disclose any structure or mechanisms for accomplishing these control functions.
Other arrangements of the LEDs within light strings are also known. U.S. Pat. No. 6,461,019 (Allen) discloses a LED light string in which a plurality of LEDs are wired in block series-parallel where one or more series blocks are each driven at the same input voltage as the source voltage and the series blocks are coupled in parallel. Allen also mentions that the individual LEDs of the light string may be arranged continuously (using the same color) periodically (using multiple, alternating CIP colors), or pseudo-randomly (any order of multiple colors). However, Allen does not provide for any control functions regarding the illumination of different colored LED within those arrangements.
Thus the need exists to provide for a LED light string controller that is capable of controlling and coordinating the specific illumination of the LEDs within the string, particularly with respect to the control of color. Further, one master LED light controller would ideally provide such control functions in an arrangement containing multiple LED light strings, while the controllers for the other light strings followed or mirrored the color selection made by master controller.